Your Roomba's bumper is not registering obstacles. You should tap the bumper to make sure it is still functioning. If the Roomba is circling, clean the wheels. If the Roomba is in a large room, use a Virtual Wall.

If the Roomba’s front wheel is having trouble turning, the wheel may have debris lodged in its axle. Remove the wheel from the Roomba and clean the wheel cavity. Also remove the wheel from its housing and clean the axle. If the wheel still does not work, it may be broken and need to be replaced.

Place the Roomba on a flat surface and restart the clean cycle. If the error also occurs on a flat surface, check the wheel to see if it is clogged with debris. Turn the wheel by hand and push the wheels up and down to dislodge any debris obstructing the wheel. If the wheel still does not work, it may be broken and need to be replaced.

I cleaned terminals, tried charging with cord plugged directly into Roomba, holding Spot and Dock for 10 seconds, etc and ordered a new battery from Amazon. Then I found one random chat where someone suggested pressing and holding Clean for about 30 seconds. I did that, the Roomba 535 made a dah dah dahhh sound and then I plugged in the cord and it now charging. I then cancelled my Amazon order.